Targeted and localized delivery of drugs is a goal of the medical and pharmaceutical industries. In targeted drug delivery the aim is to optimize drug efficacy by localizing its therapeutic effect to the diseased or infected site or organ of action. A successfully targeted therapeutic provides a significant reduction in drug toxicity, reduction of the drug dose, and increased treatment efficacy as compared to, for example, those therapeutics that may not be specifically targeted to a diseased tissue or organ. Decreased bioavailability of drugs is often a consequence of their non-specific nature. Further, drug efficacy depends upon the ability of the drug to reach its target in sufficient quantity to maintain therapeutic levels for the desired time period. Accordingly, there is a need for new compositions and methods for localized and targeted delivery of therapeutics that are not subject to the same physiological impediments often encountered by, for example, drugs that do not efficaciously impart their therapeutic effect to their intended target.